An investigation of PIA (persistant ionization in air) plasmas using room air

Summary form only given. It is now possible to create glow discharge-type plasmas in room air. These plasmas are made in a modified 1 kW microwave oven (2.45 GHz) and can be sustained for an indefinite period by the microwaves. When the microwaves are turned off the plasma continues to emit light with an exponential decay of time constant of 60 milliseconds. Plasmas occur as mobile spherical regions of approximately 3 cm radius or can be stabilized as liter sized volumes in steady state. Vortex motion appears to occur in the plasmas. The plasmas are created by a spark UV source with or without Argon gas to promote ionization. Measurements using Langmuir probes and microwave sensors have obtained an approximate electron number density of n/sub e/=5/spl times/10/sup 10/ cm/sup -3/ and an approximate electron temperature of Te=0.7 eV. A large plasma has also been made using room air in a gas vortex stabilized configuration using 45 kW at 915 Mhz. We believe these plasmas are a new and unusual plasma state first reported by Manwaring, Powell, and Finklestein (l970) who used 30 kW of RF power at 75 MHz. Recent research results will be shown.